When connecting with a MariaDB and/or MySQL Client I can see connection attributes being sent in the network packets, but I don't see them in P_S.

mysql [localhost:11000] {msandbox} ((none)) > SELECT * FROM performance_schema.session_connect_attrs;

Empty set (0.002 sec)

I tried multiple versions of MariaDB with dbdeployer on Fedora 37

Looking at the docs ( https://mariadb.com/kb/en/performance-schema-session_connect_attrs-table/ ) it seems that this should work.